1. Field of the Invention
The present invention relates to a device, for use in a chain saw, the device fastens a guide bar that supports a saw chain on a peripheral portion thereof to a chain saw body.
2. Description of Related Art
A chain saw is configured to secure a guide bar, which supports a saw chain on a peripheral portion of the guide bar, to a chain saw body with a bolt member and a nut.
Japanese Laid-open Patent Application Publication No. 2006-103301 discloses a guide bar fastening device, in which a guide bar is manually fastened (and unfastened) by rotating a semicircular lever, that is supported to a semicircular rotating knob in a diametral direction thereof, the knob being integrally secured on a nut fastening the guide bar, to thereby rotate the nut.
However, in such a guide bar fastening mechanism, a length of the lever is short because the length is limited by the size of the rotating knob, and accordingly, it might be difficult to achieve a sufficient fastening force. It might be difficult to enlarge the rotating knob because the size of the knob is limited by the size of a chain cover.